Rotating fan draft for boilers



Feb. 10, 1925.

t R. c. LAYFIELD ROTATING FAN DRAFT FOR BOILERS Filed June 24, 1924 gmemto a II/l/l/lllll/III lllleyfald m may? Patented Feb. 10, 1925,

ROY C. LAYFIELD, 0E EUFAULA, ALABAMA.

ROTATING FAN DRAFT Application filed June 24, 1924.

To all whom it may concern:

Be it known that I, ROY C. LAYrInLD, citizen of the United States, residing at Eufaula, in the county of Barbour and State of Alabama, have invented certain new and useful Improvements in Rotating I -an Drafts for Boilers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved construction of a rotating fan for providing the necessary draft in stationary or locomotive boilers.

An object of the invention is to provide a rotary fan adjacent the smoke box of a boiler, and in line therewith for creating a draft in the boiler by drawing the smoke from the fire box through the boiler tubes into the fan, and through a smoke conveyor tube to the rear of the fire box, thereby pro viding a highly efficient draft circulation for the boiler.

A further object of the invention is to provide a rotary fan adjacent to and in alinement with the smoke box of a boiler, and to operate said fan either by steam, compressed air, electricity or belt, so that the smoke from the fire box will be drawn through the boiler tubes, through said fan and through a smoke conveyor tube to the rear end of the fire box, thereby providing for a complete draft circulation through the boiler.

Other objects will appear as the description proceeds.

In the accompanying drawings which form part of my application,

Figure 1 is a side elevation of a locomotive boiler showing my improved rotary fan draft appliance in position thereon.

Figure 2 is an end view of the rotary fan draft device, with the front of the fan casing removed, and,

Figure 3 is a sectional view taken on the line 33 of Figure 2.

Like characters of reference are used throughout the following specification and the accompanying drawings to designate corresponding parts.

It will be understood that my improved rotary fan draft device may be applied to its stationary or locomotive boiler, and in FOR BOILERS.

Serial No. 722,156

this application I have shown same applied to and used in conjunction with a. locomotive boiler. A boiler 1 is provided at its forward end with the usual smoke box 2, and

at its rear end with the usual construction A fan casing 8, of the same diameter as 1 the boiler 1 is positioned at the forward end thereof in front of the smoke box 2, and has the back of its casing perforated at 9 so that the smoke from the fire box may be drawn through the boiler tubes and into the smoke box, and then through the perforations into the casing. A fan 10 is rotatably mounted in the casing 8 in suitable bearings 11, and is driven either by steam, compressed air, electricity or by belt, but in my drawings I have illustrated the same as being driven by a small steam engine 12 which receives its supply of steam through the supply pipe 13. An exhaust tube 14 is formed on the fan casing 8 adjacent the top and to the left side thereof, and is provided with an adjustable cover 15, which may be closed when the locomotive is passing through a tunnel so that sparks from the fire will not be emitted from the tube. A screen 16 of approximately one eighth inch standard wire netting is disposed between the fan casing 8 and the exhaust tube 14 so that sparks may be arrested.

A discharge tube 17 is formed at the lower side of the casing 8, below the tube 14, and is connected by means of a smoke conveyor tube 18, which terminates at the rear end of the fire box 3 directly beneath the drop bottom 6 in the coal receptacle 5. In operation the rotary fan 10 is rotated by means of the engine 12, which creates a draft in the fire box and which draws the smoke through the boiler tubes and into the smoke box, after which it will pass into the fan casing and be discharged through the smoke conveyor tube to the rear end of the fire box. The draft thus created will provide a com plete circulation throughout the boiler, and when the operating lever 7 is manipulated to drop the bottom 6 of the coal receptacle the draft from the smoke lire tube 18 Will materially assist in the feeding in of the coal from the said receptacle and spreading the same over the bed of the. It will therefore be seen that this is a complete departure from the present system used in locomotives, as they previously have had the draft through the fire and boiler created by the exhaust steam emitted inside the smoke box through an exhaust pipe Which has an opening directly in line under the center of the smoke stack. The exhaust emitted in this manner fills the smoke stack and creates a partial vacuum in the smoke box which creates the draft on the (ire. With my device the exhaust steam may be piped to a condensing tank instead of having it wasting by emitting it in the smoke box for creating the draft.

Many minor changes in detail of construction may be resorted to without departure from the spirit of the invention.

Having thus described my invention What- I claim as new and desire to secure by Let ters Patent oi the United States is:

In a boiler construction the combination with a tire box a. coal receptacle adjacent thereto, a smoke box and intermediate boiler tubes, of a rotary tan and casing of substantially equal diameter as said boiler positioned in front of said smoke box, means for rotating said fan said casing having communicating perforations with said smoke box, a top fan exhaust tube connected with said fan casing, a screen positioned between saidcasing and tube, an adjustable cover for said tube, and a smoke conveying tube connected at the lower portion of said tan casing and. extending back toand terminating at the bottom of said coal receptacle.

In testimony Whereotv I aiiix my signature.

nor 0. LAYFIELD. 

